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Blue Nile Signature Cushion-Cut Diamonds
Signature Cushion-Cut Standards
Hearts and Arrows
All Blue Nile Signature Collection diamonds are accompanied by a Certificate of Authenticity issued by the Gem Certification & Assurance Lab (GCAL) in addition to being graded by the Gemological Institute of America (GIA) or American Gem Society Laboratories (AGSL). This provides you a second authoritative analysis of your diamond and verifies that your diamond meets all the specific quality requirements of the Blue Nile Signature Collection, including an optical light performance profile. All Signature diamonds are inscribed with the Blue Nile logo and the unique certificate number on the girdle, visible with magnification.
Learn more about the Blue Nile Signature Difference. View cushion-cut diamonds from our Blue Nile Signature Collection.